(noun)
a canopy or covered structure over the entrance of a building such as a theater/theatre or hotel;
e.g. The car parked beneath the marquee of the hotel and the passengers got out.
(noun)
a sign near or above the entrance of a building such as an arena or theatre that provides information such as players/performers or attractions at the venue;
e.g. The lead actors' names are on the marquee under the name of the show.
(adjective)
famous or having the status of being a star, associated (or as if associated) with having one's name recognized and presented on a marquee as an attraction;
e.g. He is the marquee athlete of the team, its strongest player.